After using Komodo as his Python IDE for Psiphon development this term, Pat Smith provides his review below.

I find the interface to be easy to use, when I first ran the program,
I had no problem figuring out what was what. Setting up the debugger
was also easy, there is included documentation (in html) accessible
from the 'start page' of Komodo. By just following those instructions
I got the interpreter and python shell working properly in Komodo.
Running code from Komodo can be slower then running it from the
command line, by a factor of maybe 4-5 seconds, which can be pretty
annoying when you just want to run a test very quickly. So in
general, I have a shell open as I code, and run my code directly from
the command line. I know its not fully using the features of Komodo,
but that slow down can get quite frustrating.
However, one good thing about running from Komodo is that, if an error
does occur, it not only opens up files where the error occurred, but
also highlights the lines of code where the error occurred. I found
this especially helpful when I was trying to track down the Unicode
errors in PythonCard since it would open up the PythonCard files
associated with the problems and highlight the errors there.
In my opinion, the best feature of Komodo (for Python development at
least) is the indentation and syntax errors. If there are any errors
in the python code (syntax errors to be more specific), the problem
line of code is underlined in red (like MS Word's spell check), and
includes a helpful tooltip message, this saved me lots of time which
would have been used tracking down these errors during testing. So
fixing these errors as I write them is a huge help.
Komodo also has a 'smart' autocomplete tool. So as I write my code,
it brings up a box of suggested code to be filled in. Very similar to
my experience with visual studio .Net. The autocomplete tool would
learn the functions of the modules I was writing, however, I often
found it to be an annoyance since it covered up quite a bit of my own
code, and I often didn't want anything from the list of functions it
suggested, and instead needed to see the code that the box was
covering.
Running a python shell in Komodo does not appear to have any speed
slow downs like the ones mentioned above for running my program, so
doing little tests in the shell was no problem at all.
But the syntax/indentation was the most helpful, and for $30, the time
saved by fixing errors as I do them, is definately worth it!
It also catches line Windows vs. Unix new line problems.